ROUND TRIPPER: Carlos Beltran of the Cardinals slugs a two-run home run in Game 1 of the NLCS last night in San Francisco. Photo: Reuters

ROUND TRIPPER: Carlos Beltran of the Cardinals slugs a two-run home run in Game 1 of the NLCS last night in San Francisco. (
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SAN FRANCISCO —Carlos Beltran just keeps on hitting, and like everyone else, he has taken notice of Alex Rodriguez’s woeful postseason problems.

Beltran’s two-run home run in the fourth inning last night proved to be the difference in the Cardinals’ 6-4 victory over the Giants in Game 1 of the NLCS at AT&T Park. This was his 14th postseason home run in 29 games.

The ex-Met owns the all-time postseason at-bats per home run ratio of 7.71. Babe Ruth is next at 8.60. Beltran hit .444 in the NLDS. This was Beltran’s third home run of this postseason. This is the kind of production the Giants hoped they would get from Beltran when they traded Zack Wheeler for him in 2011.

The veteran knows what it takes to succeed and he believes A-Rod’s problems are from the neck up. A-Rod is 3-for-23 this postseason.

“Talent-wise, [Rodriguez] is the same,’’ Beltran told The Post.

Beltran then pointed to his head and said, “Sometimes it’s all here. You try to do too much, no matter how long you play this game, whether you are a rookie or a 17-year veteran, we all go through it.’’

That’s what he believes A-Rod is going through now.

“Alex is a great guy, a professional,’’ said Beltran, a free agent the Cardinals signed to replace Albert Pujols. “Being able to play in New York is just different. Playing in New York is just another world. I believe if you can play in New York and do well, anywhere else is a piece of cake.

“For Alex, I believe, he can help the [Yankees]. It’s not like everyone there is raking,’’ Beltran said. “I mean there are a lot of guys hitting a buck something. But being the player that he is, they expect a lot from him; not only the organization, fans, and I believe he expects a lot from himself.

“I got the opportunity to work with Alex in the off-season in 2003 and that guy works,’’ Beltran said. “He really takes pride in what he does. Sometimes you are going to be a good ballplayer. Sometimes you won’t be a good ballplayer.’’

Beltran took the called strike heard around the world in 2006 with the Mets to end the NLCS against the Cardinals. He’s on a tear now. He has tried to keep it simple this postseason.

“In these games, I am not going to do more than I am capable of,’’ Beltran said. “I don’t feel the pressure. It’s hard for me to explain this production. I’m just enjoying myself. Because, as a player, in my 15-year career, this is only the third time that I’ve been in the playoffs.

“You really have to enjoy the moment because you never know when it’s your last chance. I know if I am healthy I am going to do well. I feel good right now.’’

Noted veteran Lance Berkman, who was a teammate of Beltran’s in Houston, “Carlos has gotten the chance to demonstrate to a national audience his skill set, when he gets hot he can carry a team.’’

Beltran loves playing for St. Louis and with these teammates. “These guys have this mentality of no panicking,’’ he said.

Beltran is replacing Pujols, but he doesn’t look at it that way.

“We are two different ballplayers,’’ Beltran said. “He was an unbelievable player for this organization. I just told myself I can’t go there and get caught up in this comparison. I have to be me and play the game the way I always play, focus on realistic goals. You can’t say, ‘Well, Pujols left. He used to hit 45 home runs so I have to come here and hit 45.’ No, that’s not me. I’ve always been a player who is around 25-30 homers. I have to do my job and stay healthy. That is something I put in my mind and I never got away from that.’’

Beltran has stayed relaxed with the Cards, something Rodriguez has not done with the Yankees.